Lilium bulbiferum reaches on average 20–90 centimetres (7.9–35.4 in) of height, with a maximum of 120 centimetres (47 in). The bulbs are ovoid, with whitish large and pointed scales and can reach about 1.5 centimetres (0.59 in) of diameter. The stem is erect, the leaves are lanceolate, up to 10 centimeters long. The inflorescence has one to five short-haired flowers. They are hermaphroditic and scentless, have six upright tepals, the outer are slightly narrower than the inner ones. The flowers can reach 4–6 centimeters in length and are bright yellow-orange with reddish-brown dots. The stamens are erect, about half as long as the tepals, with red anthers. The style is orange, 35 millimetres (1.4 in) of height. The flowering period extends from May through July.
There are two varieties, L. b. var. croceum (Chaix) Baker in the western part of the range, and L. b. var. bulbiferum in its eastern part. Only the last one always produces secondary aerial bulbs (bulbils) in the axils of the upper leaves. These bulbils fall to the ground and mature after two to three years. When manually separated from the stem they can easily used for propagating the plant.
The dwarf plants from the Maritime Alps, formerly described as var. chaixii (Elwes) Stoker, and the large plants from the region of Naples, formerly described as var. giganteum N. Terracc., are now considered as local variants of var. croceum.